This invention relates to cervical braces and, more particularly, to a novel and unique cervical brace which achieves and maintains a specific alignment of the cervical spine to relieve mechanical stress on the spine and its supporting soft tissue structures during recovery from certain cervical injuries and painful disorders.
Many types of cervical braces have been developed to aid in proper cervical alignment during the recovery process following injury and/or surgery to the soft tissues, bones, and joints of the neck. The principal goal of any cervical brace is to assist in maintaining "proper" cervical alignment despite the usual bodily movements incurred throughout the day and night activities of the wearer, and to accomplish this in the most efficient and comfortable manner possible.
A growing number of spine clinicians and an increasing list of clinical research studies are recognizing the value of maintaining the lower cervical spine in extension by establishing and maintaining the head in a more retracted (posterior) position. This position is achieved by translating the head posteriorly (termed "retraction" in the art) such that the ear lobes are directly superior to the point of the shoulders, while the shoulders remain in a square "military" position (i.e., not drawn forward).
For most soft tissue injuries to the neck, achieving and maintaining this head position allows for more rapid healing and faster recovery, presumably due to the avoidance of additional cumulative stress on the lower cervical spine occurring with the partial, lower cervical flexion that accompanies a protruding head position. This protruded head position occurs as a result of either patient choice and/or habit, the nature of the injury, or consequentially from the nature of the brace selected by the clinician. Rigid control of horizontal and coronal head rotation, and upper cervical flexion and extension, has not been demonstrated to be critical in this type of soft tissue injury.
Other cervical braces, both current and past, typically include a chin support structure to keep the head from dropping forward and to minimize or eliminate head/neck movements in sagittal, axial, and coronal rotation. This is accomplished through use of a chin support rigidly mounted to, and extending upwardly from, an upper body harness. The back of the head is usually likewise supported by a second, posterior support anchored to and extending upwardly from the posterior portion of the harness. The chest and upper and middle back are utilized as anchor points for the chin and posterior supports to provide upward forces at the chin and posterior head, respectively. Examples of such an apparatus may be seen in U.S. Pat. Nos. 2,904,040 to Hale; 2,735,424 to Benjamin; 5,003,968 to Mars; and 5,046,490 to Young et al. Cervical bracing of this type is most commonly utilized for certain fractures but is awkward and bulky to wear. Also, such braces often require the assistance of a second person, or even a professional, to put on and take off, which is a time-consuming task that may detract from compliance. Furthermore, a relaxed wearer's head often still becomes protruded since the upward force provided by the chin supports does not prevent this protrusion.
"Soft" collars, commonly used in the treatment of cervical soft-tissue injuries, often referred to as "whiplash", do not anchor themselves to the thorax. They consist of a padded, wrap-around support that encases only the neck, providing only a moderate hindrance to sagittal (i.e., back and forward) and coronal bending, and minimal hindrance to horizontal rotation. Soft collars also do not limit protrusion of the head which commonly occurs due to the wearer's choice and/or habit.
Lastly, the PHILADELPHIA.RTM. Collar is a semi-rigid, two-piece anterior/posterior clamshell support which gains support and some stability by resting on the shoulders but does not anchor to the thorax. After they are positioned, the two components fix to one another by the use of VELCRO.RTM. fasteners. The collar incorporates the chin by cupping it with the superior extent of the anterior half of the collar. Posteriorly, the collar extends upward to support the lower occiput for greater control of head movement. Due to its rigidity, chin control, occiput support, and contoured support over the shoulders it is much more effective than the soft collar at hindering rotational movement in all planes. It does not, however, adequately control protrusion.